HP LTO 4 FC Recommended Get Drive Status polling frequency, ACI protocol communications retry

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HP recommends configuration of the upgrade protect features to enabled. (the Upgrade Protect bit of the Set Drive Configuration command is set to 1). This will ensure that if a firmware upgrade cartridge is loaded inadvertently, the drive’s micro-code will not be upgraded unnecessarily.

If requested, HP will alter the default settings for Auto-Eject, Auto-Load, Auto-Thread, Clean Protect, and Upgrade Protect features in your particular variant of the firmware.

Recommended Get Drive Status polling frequency

HP recommends that the polling frequency of a Get Drive Status command should be in the range 2–5s, particularly during cartridge loading and unloading. This frequency should be sufficient to capture state changes in the drive while not adding significant processing overhead to the drive or automation controller.

ACI protocol communications retry

The ACI protocol specifies a comprehensive packet retry mechanism. Under certain timing conditions, especially for automation controllers that use a single microprocessor and multiplex the ACI communications from one tape drive to another, the automation controller can receive a response packet from the tape drive that it does not need. When this situation arises, the automation controller should send a positive acknowledgement control character, <ACK>, to the tape drive and discard the packet. Since the tape drive receives the <ACK>, it will not re-send the packet.

Upgrading the drive firmware

There are three methods of updating the firmware in the tape drive:

Firmware upgrade via tape

It is expected that firmware upgrades via tape will be done under the control of the library controller and the Operator Control Panel and independently of the host interface.

If the Upgrade Protect bit is set to 1 in the Set Drive Configuration command (which is recommended), the tape can be loaded into the drive in the usual manner, except that the ACI Load command must be sent to the drive and the Upgrade bit and Thread bit in byte 1 of the Load command must be set to 1.

If the Immediate Response bit in the ACI Load command is not set to 1 and the firmware upgrade failed (say due to an invalid image on the tape), the ACI Load command will report a CHECK CONDITION with appropriate sense key and additional sense.

If the Immediate Response bit is set to 1 and the firmware upgrade fails, the automation controller can detect the failure by noting that the Tape Activity field in the Get Drive Status response returns to Idle and the tape drive does not enter its ACI initialization procedure.

•While the drive is preparing to upgrade the firmware, it will report Tape Activity = “Code Update in Progress”.

•While it is actually upgrading the firmware, the drive will not respond to ACI commands.

•After the firmware upgrade has completed the drive will reset and send out an ENQ byte over ACI.

After performing a firmware upgrade via tape it is recommended that the library controller checks that an ENQ byte is sent by the drive after it power-cycles at the end of the firmware upgrade

HP LTO Ultrium 4 drives technical reference manual, volume 2: software integration 45 HP restricted

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Contents LTO 4 FC, SCSI and SAS drives volume 2 software integrationHP LTO Ultrium tape drives technical reference manual HP restrictedLegal and notice information 1 Designing backup applications Contents2 Configuration and initialization 3 Use of tapes4 Factors affecting performance 5 Supporting Ultrium features7 Exception handling 6 Sense keys and codesHP restricted Documentation map Related documentsDocuments specific to HP Ultrium drives Drives-generalOperation Installation and configurationCartridges InterfaceDealing with errors Maintenance and troubleshootingGeneral documents and standardization LTO Ultrium featuresNon-immediate commands 1 Designing backup applicationsOptimizing performance Large data transfer sizeManaging the use of tapes Cleaning tape headsInformation in Cartridge Memory Monitoring tape useDiagnostic logs Design goals for LTO backup applicationsTapeAlert Displaying drive informationInclude the capability to download firmware 2 Configuration and initialization Inquiry string recoveryOperating system drivers Example 16 Configuration and initializationSCSI protocol, regardless of transport or interface type Support for additional LUN Enabling additional LUN supportSupporting additional LUNs 18 Configuration and initialization Using MODE SENSE Using Cartridge Memory attributes3 Use of tapes LTO cartridge memoryTape status and capacity Finding the remaining capacityInterpreting Log Sense data Using the SET CAPACITY command Command descriptor blockCDB fields WORM media Changes to SCSI commandsHow WORM media works New additional sense codes and TapeAlert flagsERASE commands rejected Error Usage pageSET CAPACITY command Re-writing media labelsUsing CM to check tape integrity Behavior with a missing or inconsistent EOD valueUnique media identifier Responding to Cartridge Memory data Load countBarcode support Corrective action RWW retry countsWays of optimizing performance 4 Factors affecting performanceDetecting the drive’s speed Ensuring the recommended minimum transfer sizesUsing the Performance Log page for diagnosing problems Using Cartridge Memory instead of tape headersTime-out values Media type identificationRecommended support of log pages Factors affecting performanceHost-related factors Recommendation Examplewhere possible or a reasonably sized RAID system. More disks means makes sense to split heavily used FC cards across separate PCI bussesDo not interleave write commands with other commands, such as READ Drive-related factorsFormat-related factors Page 34 Factors affecting performance Cartridge Memory LTO-CM 5 Supporting Ultrium featuresAutomation interface Further informationAutomation/Device Interface ADI Automation Control Interface ACI Modes of usage through ACISlave to a library controller ACI command set ACI commands that affect drive streaming performanceSCSI pass-through mode Backward compatibility New features in ACISCSI command Encryption support Supporting the ACI protocol Further detailsRecommended ACI time-out values 42 Supporting Ultrium featuresTreatment of reserved fields Recommended power-up sequenceRecommended load-unload configuration Recommended Get Drive Status polling frequency Firmware upgrade via tapeACI protocol communications retry Upgrading the drive firmwareFirmware upgrade via ACI Firmware upgrade via the primary host interfaceLibrary firmware upgrade via tape Handling irregular cartridgesExpired cleaning cartridge HP-configured or Universal Cleaning cartridge HP-configured or UniversalNon-HP Ultrium 1 cleaning cartridge Unreadable data cartridgeData cartridge with unreadable CM Valid firmware upgrade cartridgeCartridge fails to seat or load Cartridge cannot be loadedCleaning Frequently asked questionsInvalid firmware upgrade cartridge Is there separate firmware for drives intended to go into libraries?Resetting drives Backup softwareResetting via the ACI Reset command Resetting using the ACIRSTL lineControlling data compression Accessing Cartridge Memory without threading the tapeOther mode page information Buffer size at EW-EOMWrite delay time Rewind on resetPartition size 52 Supporting Ultrium featuresSense keys-actions to take 6 Sense keys and codesAction Console MessageFor additional sense codes, see “3h-MEDIUM ERROR” on “3h-MEDIUM ERROR” on page 62 . Also see the Media Accesslog the error, terminate I/O to the drive, and pass the appropriate error to the calling applicationConsole Message ActionAction Console MessageAction Physical Additional sense codes-actions to takeEnd-of-Tape reached, unable to fit0h-NO SENSE 2h-NOT READY 1h-RECOVERED ERRORLUN not accessible, port in The software must issue a LOAD before media accessThe command cannot be executed because the specified 60 Sense keys and codesmechanism tests are being executed. When the tests are 3h-MEDIUM ERROR A READ , SPACE , WRITE or WRITE FILEMARKS command62 Sense keys and codes and the drive. Based on this, ask the user to clean the Send a console message that an unrecovered error on64 Sense keys and codes Send a message to the console indicating that there is 66 Sense keys and codes The current command such as READ, SPACE, REWIND4h-HW ERROR 5h-ILLEGAL REQUEST A MODE SELECT parameter list sent to the drive contains68 Sense keys and codes persistent reservation using the PERSISTENT RESERVE OUT 6h-UNIT ATTENTIONallowed to execute. In other words, some commands can 32 initiators to register, using PERSISTENT RESERVE OUTAction A PERSISTENT RESERVE OUT command was executed service action removed all reservations and the persistentWRITE BUFFER or MAINTENANCE OUT command A SET DEVICE IDENTIFIER command has been successful7h-DATA PROTECTION Action 8h-BLANK CHECK Bh-ABORTED COMMAND READ BUFFER commandrelated to a missing EOD data set. The most likely cause Dh-VOLUME OVERFLOW A WRITE or WRITE FILEMARKS command has encountered76 Sense keys and codes 1. Retrieve fault information Typical escalation procedure3. Allow the user to try recovery 4. Allow the user to reset devicesSupporting TapeAlert Monitoring the condition of the drive and mediaType FlagsPage Page Page Page Page Page Page TapeAlert models Designing software to use the TapeAlert logReading the TapeAlert log TapeAlert polling usage modelTapeAlert informational exception usage model One-Button Disaster Recovery OBDR Responding to the ‘Clean’ LEDSupporting OBDR Requirements for drivers and logical device managers Providing pass-through modeGlossary see ”read-while-write” Index Page Page HP restricted
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